Filtering control means



June 5, 1951 c. PETERSON FILTERINC- CONTROL MEANS 2 Sheets-Sheet 1 Filed Jan. 27, 1944 C. L mwv PETERSON INVENTOR.

ATTORNEY June 5, 1951 v 3. L. PETERSON FILTERING CONTROL MEANS Filed Jan. 27, 1944 2 Shets-Sheet 2 Fla. -2

C. Lm/v PETERSON NVENTOR.

ATTORNEY.

Patented June 5, 1951 UNITED STATES PATENT OFFICE FILTERING CONTROL MEANS 0. Lynn Peterson, Salt Lake City, Utah Application January 27, 1944, Serial No. 519,850

4 Claims. 1

This invention relates to valves, and more particularly to valves for apparatus such as filters, which control the transmission of vacuum and/or pressure influences to the filter sections.

Previous filter valves comprise a disc or plate provided with a plurality of ports, each connectedwith a section of the filter. A valve head covering the plate is provided with spaces or openings on the under side and remains stationary while the disc turns with the filter, so that successive ports will be uncovered o coincide with a space or aperture. Each space or aperture is connected with a suitable source of pressure or vacuum and as the filter rotates the pressure and vacuum influences are transmitted for pre-determined periods to the respective filter sections. However, the liquor or filtrate carrying capacity of such valves is limited, and difficulty is encountered in adequately lubricating the moving parts.

Among the objects of this invention are to provide a valve for a filter or the like which has a greater liquor or filtrate carrying capacity; to provide a valve assembly in which the path of liquor or filtrate from the valve to the receiver therefor is reduced to a minimum; to provide such a. valve by which anaccurate control of the pressure and vacuum effects transmitted to the apparatus is obtained; to provide such a valve in which the forces acting thereon are balanced; and to provide such a valve which is reliable and efficient in operation. Other objects and novel features will become apparent from the description which follows.

In accordance with this invention, a valve such as one particularly adapted to control the transmission of vacuum influences to a filter or the like, is at least partially enclosed by a vacuum receiver into which the removed liquor or filtrate passes. The path between the valve and receiver is thereby reduced to a minimum and an increased liquor carrying capacity results. Also, since the receiver at least partially encloses the valve, it is not necessary toequip the valve head with a vacuum connection, but merely an opening through which the vacuum efiect is produced directly on the valve ports, thereby further increasing the liquor carrying capacity and efficiency of the valve. Since the filtrate removed during the vacuum or suction interval necessarily passes through the valve into the receiver provided for the purpose, the filtrate or liquor carrying capacity of the valve determines the suction eiTect which can be obtained tocause solid particles. to be deposited upon the filter medium, and the increased. liquor carrying, capacity of the valve thus increases the efficiency and capacity of the filter.

In further accordance with this invention, sealing means such as packing is provided about the periphery of the rotating 0r movable portion of the valve, which packing preferably engages the head of the valve at the junction between the rotating and non-rotating parts. Also, suitable means is subjected to vacuum influence and the force thereby produced is transmitted to the valve head, tooppose the force tending to separate the valve head and plate, due to the vacuum in the enclosing receiver.

In still further accordance with this invention, a suitable lubricant is positively supplied to the surfaces of the head and plate which are in engagement with each other, and a reservoir of lubricant is provided adjacent each such surface, so that a slight accidental separation of the sur faces will not permit the vacuum. to remove all the lubricant from the surfaces without possibility of quick and easy replacement.

Other features and a specific embodiment of this invention will be apparent from a more detailed description which follows, taken in connection with the accompanying drawings, in which:

Fig. l is a longitudinal section of a valve assembly constructed in accordance with this invention, showing also a portion of the filter upon which the valve is installed; and

Fig. 2 is an end view of the valve, broken away in part at the lower side and as viewed from the vacuum receiver along line 2-2 of Fig. 1.

A valve constructed in accordance with this invention, as illustrated in the drawings, may include a plate P and a head H, enclosed by a vacuum receiver R which may be evacuated in any suitable manner. The valve controls the pressure and vacuum influences supplied through passages I 0 of a filter drum II, and each passage lll leads to a longitudinal section of the filter, the periphery of which is provided with a filter medium or cloth. The drum is rotatably mounted. in a bearing I2 supported on a beam I3, and is rotated by suitable means, such as a worm engaging a gear attached to the drum at the end opposite the valve. The plate P of the valve is attached to and rotates with the drum, and is provided with ports l4 aligned with passages 10.

For transmitting the vacuum influence from the receiver to ports l4, head H is provided with an arcuate slot 15 which extends approximately half-way around the head. Head H is also provided with spaces I 6 and 11, leading to arcuate slots l8. on the side of the head next to plate P, to communicate also with ports 14. The inner surface of head H and the outer surface of plate P are finish machined or ground, to provide a smooth surface for sealing purposes. As the drum H rotates, the vacuum effect transmitted to the peripheral drum sections corresponding to the ports uncovered by slot l5 causes filtrate to be drawn through the filter medium and pass into the receiver R. When the ports pass beneath arcuate slots I8, different degrees of vacuum, air or steam under pressure, or the like, may be transmitted through the ports to the respective filter medium sections.

A cover C is attached to head H in a suitable manner, as by bolts, and closes spaces 16 and H. The cover C is provided with connections I 9 and 26 which lead to spaces I6 and I! and to which tubes or hoses 2| and 22, respectively, are attached. The head is provided with reinforcing ribs 23 which extend from a central ring to a rim 2-; and also form side walls about spaces l6 and I1.

'I'o exert a force tending to hold the head H against the plate P, a compression spring 25 bears against the cover C through a thrust washer 25. The opposite end of the spring engages a thrust washer 21 held by a nut threaded on the end of a bolt 28, which passes centrally through the cover and head and threadedly engages plate P for sealing purposes, the bolt being provided with a lock nut to prevent rotation with respect to the plate. Normally, the force of spring 25 would be suflicient to maintain the sealing surfaces between the head and the plate in engagement.

Due to the fact that the head is positioned within the vacuum receiver R, the vacuum tends to pull the head from the plate. Therefore, in accordance with this invention, additional means is provided, and preferably means acted upon by the vacuum influence, to counteract the force tending to pull the head from the plate. Such means may include a circular plate 36, having guides 31 surrounding the closed end of a force-transmitting tube 32. An adjustable bolt 33, which may be locked in position by a lock nut 34, transmits the force from plate 36 to the rear end of tube 32. The plate 36 is attached to the vacuum receiver by a flexible connection,

such as a ring 35, formed of rubber or other suit- The front end of tube 32 bears against a peripheral flange on the end of a grease cap 31, which rests on cover C, to transmit the force produced by the pull of the vacuum on plate 30, and maintain the head H in engagement with the plate P. The area of plate 3!] is preferably so proportioned to the area of head H that the force transmitted through tube 32 compensates for the difference between the pressure exerted by spring 25 and the pull of the vacuum on the head. It will be apparent that, for different degrees of Vacuum, the force provided by the plate 36 will correspond in a direct ratio to the pull of the vacuum on the head, so that changes in the degree of vacuum which alter the pull on the head will produce corresponding changes in the force exerted by the plate, with any slight differences due to the difference in area between the plate and the head taken up by spring 25. Thus, the head will be held against the plate by substantially the same force, with automatic 4 l compensation for changes in vacuum; and changes in vacuum will not require adjustment to maintain the head in sealing engagement with the plate, so that the operating efficiency of the valve is thereby increased.

The vacuum receiver R includes a tubular axial housing 39, to the open outer end of which is attached cover 36 with a gasket interposed for sealing purposes. The housing 39 extends axially in the same direction as the drum and the valve, and is cut away at one side for attachment in a suitable manner, as by welding, to a transverse housing or drum 46, which may be suitably supported and provided with an exhaust connection along its lower side. The drum 40 preferably extends at right angles to the housing 39 and increases the capacity of the vacuum receiver. The inner end of housing 39 is flanged and a gasket interposed between the flange and a bracket 5|, the two being clamped together, as by nuts on studs 42. Studs 42 are also utilized in adjusting the pressure exerted by a ring gland 43 against packing 44 disposed beneath an axial extension 45 of bracket Al, the packing bearing against the outer periphery of drum 1 l for sealing purposes.

Since the plate P rotates with respect to head H, a thrust plate 41 is provided with an axial neck and shoulder upon which seats a bushing 48 having a flange at one end and is attached to the drum along with plate P in a suitable manner, as by bolts as shown. Bushing 48 is formed of suitable material, such as bronze, and a number of spiral grooves are formed on the inner cylindrical surface thereof, as well as radial grooves extending outwardly along the flange of the bushing. These grooves not only provide for lubrication of the bearing formed between the bushing and thrust plate 41, but also provide for transmission of grease to an annular storage reservoir 49 formed between the outer periphery of thrust plate 41 and the under side of head H. From this reservoir, grease fiows outwardly to the inner sealing surfaces 50 between the head and plate, the reservoir being sufliciently large so that if a slight separation of the head and plate should occur, even momentarily, and all of the grease between the sealing surfaces be sucked out by the vacuum, grease immediately will be supplied the sealing surfaces from the reservoir.

Grease is supplied reservoir 49 from the space around spring 25 and th end of bolt 28, within grease cap 31, a sleeve 5| being provided for sealing purposes. Grease is supplied to the interior of cap 31 by a tube 52, which extends from a fitting 53 welded or otherwise air and vacuum tightly secured to housing 39 at a point on the upper side thereof. Grease ocmpletely fills the space within cap 31, and flows through the spring and around bolt 28 to the space between the end of thrust plate 41 and the under side of cover C. From this space the grease flows through the grooves in bushing 50 to reservoir 49. The under side of washer 26 is provided with radial or spiral grooves for lubrication purposes, since bolt 28 is locked to plate P and rotates therewith, as do also spring 25 and washers 26 and 21.

To supply grease to outer sealing surfaces 55 between the head H and plate P, and also to seal the periphery of the head and plate from the vacuum receiver, packing material 56 is compressed by an annular gland 5'! against the outer periphery of the plate P and also against the face of the head, adjacent the edge thereof. The

packing material is provided with a porous central section 53 through which grease can flow to the outer periphery of the plate, and thence to the outer sealing surfaces 55.. Porous: center 58 of the packing also acts as a grease reservoir for supplying sealing surfaces '55.

Annular gland 51' may be pulled toward the head H in a suitable manner, as by a plurality of springs 55, such as three. in number and spaced equally about the periphery of the gland. One end of each spring bears against a countersink Si in head H, and the other end against a semi circular plate 51, attached to the gland in a suit able manner, as by bolts, as in Fig. 2. A guide bolt 62 is attached to each plate 6| and extends centrally through each spring 59 and into a hole centered in countersink 60, to center the spring and prevent it from slipping out of position. Three grease supply nipples 63. are threaded into the gland, and grease flows to the porous center 58 of the packing through axial holes 64 and radial holes 65 in the gland. Each nipple is connected by a tube 66 with a fitting 6'! which extends. through housing 39, and is suitably secured thereto, as by welding, fittings 61 being in alignment with each other and with fitting 53. Fittings and 61 are connected by tubes or pipes 68 with. a suitable source of grease under pressure.

To adjust the radial position of head H, in order to cause the vacuum and other influences to be exerted at desired predetermined times during rotation of the drum, a threaded block 70, as in Fig. 2,. may be pivotally attached to the cover at one corner thereof by a pin H. An adjusting. bolt 12, threadedly engaging block 70, extends through a tubular sleeve 73, which, in turn, extends through housing 39 and is joined thereto in a suitable manner, as by Welding. A

nut 14, on bolt 12, bears against the outer end of sleeve 13, to determine the relative position of the head H with respect to plate P.

The valve arrangement described herein is adapted particularlyfor use in the double drum filter arrangement of my co-pending application, Serial No. 504,831, filed October 4, 1943, and issued as Patent 2,499,412 on March 7, 1950. As disclosed and claimed therein, a body of fluent matter is maintained between the upper peripheries of a pair of drums disposed in parallel relationship, rotating in opposite directions, and contacting each other along a substantially horizontal line. The vacuum influence is exerted over the sections about the upper portion of each drum periphery, and a pressure and/or blow is maintained when .a section of the drum moves around to a point about or below the center line of the drum. To transmit the vacuum influence in the above manner slot I 5 is located around the upper portion of head H. Air under pressure may be supplied through tube 2 I, so that the deposited material will be blown off and out of the filter medium sections as the ports corresponding thereto come into juxtaposition with slot [8 beneath space It. If desired, steam may be supplied through tube 22 to cleanse the filter medium before it passes into the body of fluent matter again.

It will be understood, however, that the valve of this invention is also particularly applicable to a single drum filter in which the lower periphery of the drum is immersed in'a, body of fluent matter, and the vacuum influence is exerted from a point just below the center line of the drum to a point above the center line of the drum on the opposite side thereof. For such a filter, the

position of the head and coverwill be substantially reversed from that shown, i. e., slot [5 will be disposed along the lower portion of the head instead of the upper portion, with corresponding changes inthe position of spaces l6 and I1 and the connections thereto. It will also be understood that the extent of slot It: may be varied from that shown, and that the slot may partially or wholly replace space IE or H.

The valve of this invention is. economical and efiicient in operation, since a direct flow of filtrate to the vacuum receiver is provided, and at the same time a different degree of vacuum and/or air, steam, or the like under pressure may be supplied filter sections at other points. Also, the valve of this invention is adequately lubricated and special provision is made for overcoming the possibility of slight valve separation. Thus, the valve plate will always rotate freely with respect to the valve head, and the seal effected between the ground surfaces will be maintained in optimum condition. Furthermore, the valve is efiectively sealed from the vacuum in the receiver, and the vacuum receiver is effectively sealed from the drum.

The tendency for vacuum in the receiver to separate the head and plate of the valve is overcome by an equalizing force maintained by plate 3i! which is subject to the vacuum influence. If the vacuum in the receiver is changed, the pull upon the plate is lessened or increased in accordance with such change, thereby again compensating for the pull upon the head of the valve.

It will be understood that various changes may be made in the valve of this invention, such as in the shape and position of the parts of the valve, the vacuum receiver, the vacuum thrust 'plate, and other parts. Also, other means for overcomin the force tending to separate the head and plate may be utilized, such as a cylinder or piston arrangement, or other devices which will suggest themselves to those skilled in the art.

It will further be understood that the embodiment. illustrated in the drawings and described in detail comprises only one modification, and that other embodiments may exist. Also, various changes other than those enumerated may be made, all without departing from the spirit and scope of this invention.

What is claimed is:

1. In a filter or the like which includes a drum having a plurality of longitudinally extending peripheral sections and passages for the periodic transmission of vacuum and pressure influences to said sections, a control comprising a valve plate having ports corresponding in number to and adapted to communicate with said passages, said plate being adapted to be attached to and rotated with said drum; a valve head adapted to be held against said plate and provided with apertures for registering with successive ports as said-plate rotates relative thereto; a vacuum receiver enclosing said valve head and plate and adapted to form a joint with said drum, said receiver establishing a vacuum effect tending to separate said head and plate; a seal for the joint between said receiver and said drum subjected to said vacuum efiect; means within said receiver for effecting a seal between said head and said plate; a spring for pressing said head against said plate; diaphragm means forming a portion of the wall of said receiver and subjected to vacuum influence on one side; means for transmitting the force exerted by said diaphragm to said valve head, for opposing the tendency of the vacuum to separate said valve head and plate; and an adjustable connection between said diaphragm means and said transmitting means.

2. A filter control as defined in claim 1, including a cover attached to said valve head for conveying fluid under pressure to said apertures therein, and pressure connections extending through said receiver to said cover.

3. In a filter or the like, a control for regulating the transmission of vacuum and pressure influences, comprising a valve plate having ports; a valve head having a plurality of apertures for registering with successive ports upon relative movement between said plate and said head; a vacuum receiver substantially enclosing said valve head and plate, at least one of said apertures being open to said receiver; co-operating sealing surfaces on said plate and head within said receiver; a reservoir for-grease adjacent to said surfaces, for lubricating said surfaces; a thrust plate forming a portion of the wall of said receiver and thereby subject on one side to vacuum and on the opposite side to atmospheric pressure, said thrust plate being connected to the remainder of said wall by a flexible diaphragm; means for transmitting the force exerted on said thrust plate to said valve head for opposing the tendency of vacuum to separate said valve head and plate; and at least one conduit leading through said receiver to said head for transmitting a different degree of vacuum, air or steam under pressure, or the like, at least one aperture of said valve head being connected with each conduit.

4. A valve assembly for a filter or the like, comprising a valve plate having ports, said plate being adapted to be rotated with a drum having passages corresponding to and adapted to communicate with said ports, for the transmission of vacuum and pressure influences to predetermined portions of said drum; a valve head adapted to be held against said plate and provided with apertures for registering with successive ports as said plate rotates relative to said head; a

vacuum receiver enclosing said valve head and. plate and adapted to form a joint with said drum; said receiver establishing a substantial vacuum effect tending to separate said head and plate, a seal for the joint between said receiver and drum; means within said receiver for effectin a seal between said head and said plate; diaphragm means forming a portion of the wall of said receiver and subjected to vacuum influence on one side; means for transmitting the force exerted by said diaphragm to said valve head, for opposing the tendency of the vacuum to separate said valve head and plate; and an adjustable connection between said diaphragm means and said transmitting means.

C. LYNN PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 3,378 Kelsey Dec. 15, 1843 1,447,285 Dollin Mar. 6, 1923 1,659,699 Oliver Feb. 21, 1928 1,907,191 Thomas May 2, 1933 1,917,818 Woodworth July 11, 1933 1,929,510 Mount Oct. 10, 1933 1,946,235 Riley Feb. 6, 1934 1,948,963 Duker Feb. 27, 1934 1,998,055 Naatz Apr. 16, 1935 2,192,835 Leach Mar. 5, 1940 2,198,759 Cadet Apr. 30, 1940 2,200,154 Cadet May 17, 1940 2,238,101 Clifford Apr. 15, 1941 2,352,330 Lee June 27, 1944 2,367,319 Wahlberg Jan. 16, 1945 FOREIGN PATENTS Number Country Date 11,969 Great Britain May 23, 1907 118,688 Australia July 6, 1944 185,430 Great Britain Aug. 25, 1922 

